one of the coolest science kits in a longtime. building the circuitry to make the speakers, and you have two different cases to put your mp-3 player in, and then it's playing some music. it's actually the leapfrog that's making some noise, but it's -- the box from the laws of physics actually make it louder which is really cool. >> cool. >> now another example -- enough music. >> thank you, al. >> another lesson in circuits from laser pegs. love these sets. about $20, making them more accessible. build the models to their specs or open-ended for kids with special needs. >> jigsaw puzzles. >> one of the best uses of apps. some did not fare well but this one really works. ravens burger puzzle. build this 1,000-piece puzzle. this is something you'll want to do together, and look what happens. when he -- when he puts the ipad on the puzzle, different aspects of the puzzle come to life. >> that's very, very -- >> cool. >> my son down there loves when i say lego "star wars," educational, bring them home. that's true of all construction